1. Field of the Invention
The present invention relates generally to composite yarn products, and particularly to an adhesive composition useful in their preparation.
2. Description of the Prior Art
Generally, composite yarn products are known, and may be prepared by a variety of techniques, yielding products ranging from ribbon strips to light-conductive fibers. Thus, U.S. Pat. No. 2,166,819 to Miller prepares a two-ply ribbon strip by adhesively bonding two layers of plastic to each other and thereafter longitudinally slitting the composite product. U.S. Pat. No. 3,361,616 to Scharf discloses the preparation of a composite yarn by the disposition of actual strands of thread or strands of metalized material between two resinous sheets. Finally, U.S. Pat. No. 3,666,587 to Nagao shows the preparation of a light-conducting fiber by the preparation of a sandwich of a polystyrene material between acrylic sheet materials.
Notwithstanding the above, certain materials have been developed and are presently in wide use as yarn products, which are particularly attractive and provide a multi-colored textured hue that is desirable for incorporation in clothing fabric, drapery materials and trim accessories. In particular, such materials may comprise a cellulosic film which is given multiple iridescent coatings, to capture different reflective colorations depending upon its angle of exposure to light. This material may have as many as 120 layers of colors applied with rollers, and may be prepared to a thickness of 0.8 mil.
Certain difficulties have developed in the use of this material, as it offers a soft hand, but tends to fracture and break during manufacture and subsequent use. Attempts to strengthen this material by offering a thicker base, and by preparing composite yarn products where the film is disposed upon one or more base sheet layers, have all failed, as either the additional thickness renders the resulting yarn aesthetically undesirable and awkward to process and weave, or the incremental increases in thickness are insufficient to remedy the weakness of the yarn product.
A need therefore exists for the preparation of a composite yarn product that maintains an acceptable flexibility and texture, yet achieves an improved strength to withstand processing and use.